Layered Double Hydroxides Nanohybrid Intercalation with Folic Acid Used as Delivery System and their Controlled Release Properties

For fully controlled drug release, it is important to completely understand the microstructure and nature of the layered double hydroxide that ultimately controls drug release properties. The anion of folic acid (FA) as an organic guest was intercalated into the interlayer of anionic clay, Ni/Al hydrotalcite-like or layered double hydroxides (LDHs) as host by direct co-precipitation method from aqueous solution for the formation of new nanohybrid compound, Ni/Al–FA nanohybrids (NAHs), where, Ni/Al molar ratio R = 3 and concentration of folic acid (FA) (100 ppm) were used for the synthesis. Accumulations of 88, 78 and 72 %, as release profiles of the guest anion in carbonate, phosphate and sulphate media have been conducted, in all these media the release was governed by pseudo-second order model of kinetics. In this study, novel equations were innovated that used the prediction of diffusion of guest anion through LDHs nanohybrid particles and applied it for folic acid release. These equations were more suitable for diffusion than the previous equations such as (Bhaskar equation, the parabolic diffusion model, the modified Freundlich model etc.) and it is the best and convenient.